Flow tube differential pressure producer



g- 5, 1952 v. 'GENTILE, JR 2,605,639

FLOW TUBE DIFFERENTIAL PRESSURE PRODUCER Filed April 30, 1949 2SHEETS-SHEET 1 FIG! ATTORNEY.

Aug. 5, 1952 -v. GENTILE, JR

FLOW TUBE DIFFERENTIAL PRESSURE PRODUCER 7.

Filed April 30, 1949 2 SHEETS-SHEET 2 ATTORNEY.

l atenteci Aug. 5, 1952 snow TUBE m F nENn-ALPnEssURE PRODUCER Vincent.Gentile, Jn, Broeklyn,fN.- Y Application April30, 1949, Serial NOLJQDfiGQ. sonims. ((11. 73-272) This invention relatesto devices:for:mea'Sufihthe gyelocity or quantity rate of flowozf a, liquid.

orza gaseousmedium.

In my Patent No.. .2 ,260,019, issued October 21., 1M1, I hav disc os d.aflowtube; having roups of nozzles closely adjacent to theinnersurfaceof the tube and facing inopposite directions for measuring theflow rate or velocity of fluids, and presenting distinct advantages overVenturi tubes as pointed out in said .patent.

prcs nt nvemio p ovi e an w ac limp. r d. i ow tub havin n vel f a uresw ch con r b e t increa ed c uracy an e i ency over a wide rangeoffluid-velocity measurements.

vA f tu of heiny n ion m ri e a f ow tu e havi r ups of: n le op ni in ova central portion of afcontinuously curved section of the flow tubepassage.

Another des rab e f aturepr v d by th v t n. comprises roup aofnozziescir umicrentiahyspaced and: fac n in oppo ite. irections with thir impac openin s ini ccmmon an normal to the flow tube axis. r r

Other features and advantages of the; invention will be hereinafter,described and cia-irned,

In the, accompanying drawings:

Fighlis an, end view of a preferred enr bodiment of the invention.

Fig. 2. is a longitudinal ver ical sectional Vi w of said embodiment,takenon line -2--2 of Fig; 1.

Fig. 3 is a transversegvertical sectional view on line 3-3 of Fig. 2.

Fig. 4..is a longitudinal vertical section on line 4-4 ofFig. 1.

Referring to the drawings, a flow tube'uniti is provided of anydesirablelength and-diameter. The tube may have "flangedend portions projectingoutwardly beyond the main bodyport'ion f he tube, as in.myabove-menticned paten or, as, shown inthisapplication, .saidtube maycomprise an outer radial portionfi coextensive with the inner portion lof the tube throughout I the major part of its length, but terminatingashort distance from. the ends of said inner portion so that said endsform circular bosses 8 and 8 projecting beyond the ends of said outerportion 6, and adapted to fit firmly into the open ends of adjacent pipesections to unite the latter.

Said outer portion 6 of the tube is provided with holes .10 forreceiving bolts to fasten the tube securely to flanges of said adjacentpipe sections; as will be apparent. V

Into the inner sectionl' there :is securely fitted a tubular liner H,having its ends- 1 2 and I3 substantially coincident with the end facesof the bosses 8 and 9, as shown. From each end, the interior surface ofsaid liner H curves inwardly to the central transverse plane of theliner, thus the nozzle passage '23 .from a point above; -posite end "of:said body is -c urved as shown at providing a throat orfiow passage Mwhich decreases in cross-sectiongfrom, each end to th e; center.Preferably, the flow passage I4 has a continuous curvature from end toend; and curves uniformly inwardly from one end to the center of-thepassage, and uniformly outwardly; from thecenter' to the otheren d,tires-curvature. being preferably the same. :fromvsaid-centerto;

each of the ends. "The" curvature formediin.a;

longitudinal section of the throat or liner is pref erably a conic(circlewllipse, parabola, or hyperbola), but need not'be of anyparticular form. Nor need the curvature between one end..=a:ntl thecenter of the throat be a duplicate In the. curvature between the centerand the other end. Portions 'of the central region of the throat l4arerecessed, as indicated at Hi, to receivenozzles l6, I1, I8, 19, 2'0,and 2|. Each-nozzle-,-as-shown, may comprise a body having aninteriorradial passage 22 and a passa efiextendingtransversely from said radialpassage and opening into the throat; or flow passage M. The nozzles l6,l8, and-2l form one circumferentialgroup, having their opening orpassages 2 3pointing up I stream. Nozzles ll, f9, and- -2l'-' for1m asecond" circumferential group, the passages 213" of whieh pointdownstream. Each nozzle body has 'afii curved surface {24 extending froma peint below to an end of {said lmsdy f with curved surface preferablymerges "with the adjacent curvature of the throat M nlso. the portion ofeach nozzle body which xtendsthe passage 23 to the op-f;

25. The nozzle bodies may be-secured-inany' suitable manner. as bypress-fitting, or sweating in the respective recesses 15providedtherefor; in the liner H. I

The nozzles IBAB, and 20 are prefer-ably spaced equidistantly '(i. e.,120) fromeach-other; as arealso the nozzles l1, l9, and 21. The endsefall" of the six nozzle, passages 2 3- which --epen= into' the throatM-are in'a'common-planencrmal tothe 'centrarlongitudinalaxisofsaid-threat- Thiscommon plane is preferably equidistantfrom endsl2 and I3 of the throat. fThe passages 22 Qff the nozzles It, 4 8} gene20, communicate through intermediate passages- 26;

' with an annular -charnber-or manifold 21 in-the liner 11. *Likewisathepassages-22 of the nozzles I1, 1 9; and 21 communicate throughintermediate-f passages ZBJWith an annular-chambero ma'ni j fol'd;29.insaid liner. 'Ports. 3'0 ands l in, the flow-tube communicate with therespective annular chambers orman'ie folds 21 and .29, These portscommunicate through pipes 32,1with any suitable" manometer or otherinstrument ;,(such as shown-"at in my copending application Serial No.73438531 3 filed March 14, 1947, now Patent No. 2,573,430) responsive tothe difference between the pressures in said manifolds 21 and 29.

It will be noted that the nozzles Iii-2| are quite small relative to theinternal diameter of the throat l4 and that their passages 23 have theirend portions opening into said throat very closely adjacent to the innersurface of the throat wall.

In the measurement of the velocity or quantity rate of flow of a fluidflowing through the throat 14, there will be impressed on the upstreamgroup of nozzles a total head equal to the static head plus the velocityhead, or calling this head H,

there is obtained V H d+ where hzstatic head, and

V -=the velocity head 9 V On the downstream group of nozzles, there willbe impressed a total head equal to the static head minus the velocityhead, or calling this pressure H, there is obtained.

V2 V H h The differential head that would be recorded in this case wouldbe KL l K H H h+ (h 2g 2 This is equal to two velocity heads at thenozzles and by suitable calibration of the metering device may beconverted to read in any desired units of flow, either in terms ofaverage velocity or quantity flowing per unit of time.

The provision of the curved throat 14, into the central portion of whichthe nozzle passages extend, increases the velocity of flow past thenozzles and thus greatly increases the differential pressure (whichvaries as the square of thevelocity). Substantial increase in precisionand accuracy of measurement of the fiow rate is thereby attained.

The mounting of the two groups of nozzles facing in opposite directionswith all of their impact passages 23 in a common plane normal to theaxis of the conduit efiects further desirable advantages. It eliminatesany. frictional loss be: It also eliminates anym tween the two groups.effect on the downstream group due to any turbulence at the trailingedge of the upstream group. Accuracy of flow-rate measurement is thusadditionally enhanced. The provision of a common throat diameter forboth groups of nozzles also obviates errors in machining toleranceswhich might arise where the impact openings of, the respective nozzlegroups are spaced from each otherindifferent'parts of the flow passage.

The annular chambers 21, 29, may, as shown, be provided with drain ports35, 35, normally closed by threaded plugs 31, 38; Also, ports 40, 4|,may be drilled through they liner H, as shown in Fig. 4 and maycommunicate with ports 42, 43, which are drilled through the flow tube,for attachment to a manometer or the like, whenever measurement of thestatic pressure in the throat [4 may be desired. Normally, said ports42, 43 are closed by plugs 44, 45. i

,It will readily be seen that the illustrativ embodiment of my inventionabove described provides an economical, efficient, compact, and

4 flexible apparatus for producing a differential pressure in eitherdirection, which may be employed to indicate, record, or regulate theflow of a fluid.

The terms and expressions which I have employed are used as terms ofdescription and not of limitation, and I have no intention, in the useof such terms and expressions, of excluding any equivalents of thefeatures shown and described or portions thereof, but recognize thatvarious modifications are possible within the scope of the inventionclaimed.

I claim:

1; In apparatus of the character described, a conduit having a curvedinterior throat for the passage of a fluid, said throat being curvedi'nwardly from opposite ends toward the center thereof, two groups ofnozzles within said curved throat and adjacent the wall thereof, thenozzles in each group being circumferentially spaced apart, each of saidnozzles having a bore opening at one end into said throat, the bores inthe nozzles of the respective groups facing in opposite directions, andthe open ends of said bores in the nozzles of both'groups being in acommon plane normal to the longitudinal axis of said a conduit.

2. In apparatus of the character described, a conduit having a curvedthroat for the passage of a fluid, said throat being continuously curvedinwardly from opposite ends to a'central portion thereof, two groups ofnozzles adjacent the wall of said throat, the nozzles in each groupbeing circumferentially spaced apart, each of said nozzles having a boreopening at one end into the central portion of said throat, the bores ofthe nozzles 0f the respective groups facing in opposite directions andthe open ends of said bores in the nozzles of both groups being in acommon plane normal to the longitudinal axis of said conduit.

3. In apparatus of the character described, a conduit having a curvedthroat for the passage of a fluid, said throat being continuously curvedinwardly from opposite ends to a central portion thereof, two groups ofnozzles in said throat and adjacent the wall thereof, the nozzles ineach group being, circumferentially spaced apart, each of said nozzleshaving a bore opening at one end into the central portion of saidthroat, the bores of the nozzles of the respective groups facing inopposite directions and the open ends of said bores in the nozzles ofboth groups being in a common plane normal to the longitudinal axis ofsaid conduit, means comprising a first manifold communicating with thebores of the nozzles in one of said groups for receiving pressuretherefrom, and means comprising a second manifold communicating with thebores of the nozzles in the other of said groups for receiving pressuretherefrom.

' VINCENT GEN'I'ILE, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

. UNITED STATES PATENTS vDate

